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**How to write design matrix and contrast for continuous variable analysis (not comparison between groups)**Jul 20, 2021 08:07 PM | Qiushi Wang

How to write design matrix and contrast for continuous variable analysis (not comparison between groups)

Hello everyone,

I have checked the manual and the forum posts, as I am not doing comparison between groups or longitudinal analysis ( I do continuous variable analysis use cross-sectional data), so I am a little confused about the writing of design matrix and contrast.

I used a set of cross-sectional data to explore which edges in the FC matrix had significant age effects. Specifically:

I have a group of subjects with different ages (suppose 5 people), and I want to examine which edges develop significantly with age (subjects are not divided in to groups but put together). Meanwhile, sex and FD are used as covariates. How should I write design matrix and contrast?

In addition, I have two simple questions and I'm not so confident about: (1) Dose the value filled in the “Threshold” box a T statistic? For example, if I have 5 subjects and I want to identify the significant edges at p=0.01, according to df=5 and p=0.01, 4.032 should be filled in here. If I want p=0.001 as the significance level for the edges, then 6.869? (2) Does the value filled in the "Significance" box correspond to the P value of the Component (not the P value for the edge)?

Thank you very much!

Best wishes

Qiushi

I have checked the manual and the forum posts, as I am not doing comparison between groups or longitudinal analysis ( I do continuous variable analysis use cross-sectional data), so I am a little confused about the writing of design matrix and contrast.

I used a set of cross-sectional data to explore which edges in the FC matrix had significant age effects. Specifically:

I have a group of subjects with different ages (suppose 5 people), and I want to examine which edges develop significantly with age (subjects are not divided in to groups but put together). Meanwhile, sex and FD are used as covariates. How should I write design matrix and contrast?

In addition, I have two simple questions and I'm not so confident about: (1) Dose the value filled in the “Threshold” box a T statistic? For example, if I have 5 subjects and I want to identify the significant edges at p=0.01, according to df=5 and p=0.01, 4.032 should be filled in here. If I want p=0.001 as the significance level for the edges, then 6.869? (2) Does the value filled in the "Significance" box correspond to the P value of the Component (not the P value for the edge)?

Thank you very much!

Best wishes

Qiushi

## Threaded View

Title | Author | Date |
---|---|---|

Qiushi Wang |
Jul 20, 2021 | |

Ben Sipes |
Aug 31, 2021 | |

Andrew Zalesky |
Sep 1, 2021 | |

Ben Sipes |
Sep 1, 2021 | |

Andrew Zalesky |
Jul 20, 2021 | |

Qiushi Wang |
Jul 21, 2021 | |